Automatic case stacker



Oct. 21, 1958 w. s. CAMPBELL '2,857,040

` AUTOMATIC 'CASE STACKER Filed Apri1 5, 1956 4 Shee1'.s-Sheel:'1

IN V EN TOR.

Oct. 21, 195s Filed April 5, 1956 w. s. CAMPBELLv AUTOMATIC CASE STACKER 4 sheets-sheet 2 I 1N VEN TOR.

Oct. 21, 1958 w. s. CAMPBELL 2,857,040

y AUTOMATIC cAsE STACKER Filed April 5, 195e 4 sheets-sheet s Oct. 21, 1958 Filed April 5, 1956 INVENIOR.

AUTOMATIC 'CASE STACKER Willard S. Campbell, Chicago, Ill., assignor to M. & C. Conveyors, Inc., Chicago, Ill., a corporation of illinois `Application April 5, V'1956,'Seiial No.5*7'6,493 -2 Claims. (Cl. 198-3-75) My invention relates to an automatic case stacker adapted to stack milk bottle cases, or the like.

In -dairies and other plants where milk or other iluids are bottled and placed in cases, it is necessary to move these cases from place to place, In such ksituations it is a great saving -of time, and labor t move the cases in stacks, rather than one lat a time. For instance, let us say that the cases have been loaded with lled bottles and it is necessary to move them to a storage room, or to a cooler, or to a truck upon which they are tobe loaded for shipment. vIf the cases are stacked one on top of another to a stack of let us say ve cases, it is much quicker to pull the stack than to pull ve separate cases. Ordinarily a worker operating with the usual hook can pull a stack/of tive cases with less back breaking etort than a single case. This is because the stick Yattached to the hookcan be raised so thatthe Worker can pull the stack in upright Zposition. The amount ottime, and labor saved in moving stacked cases is substantial. However, the lifting of the cases, to stack them, yparticularly'when loaded with 'lledbottlea presents a fproblem.

Among the objects of my invention is to solve the foregoing problem, tand to provide a stacker for automatically stackingcases and-'movingthem to desired position.

My invention also contemplates suc'hlother objects, .advantag'es, yand capabilitiescaswill later morefullyappear and Which' are Iinherentlyl possessed byqny invention.

While I 'have shown `in the laccompanying drawings, -a preferred fo'rm of my invention, yyetit isto'be -understood that the Ysame is s'usceptible'of modification and change Without'departing from the spirit'of rmy invention.

nited States of 'myfautomatic case stackerg-Fig. 2 is'an 'endl-elevational viewln csection, on fline Af2hf2=of Fig. Y1, `Fig. 3 ris Ea side elevational View; Figs'4' and 5 Fare zenlargedlviews Vof 'fthe case fstop; eFig. '16 is a @detailed 'vie'wxon line 6==6 of Fig. 4; andFig. 7 is aschern'ati@diagrammatic viewshowi'ngfthelsyst'em operation.

The *embodiment r`selected to illustrate my invention comprises fafcaseconveyor T10 fand c'asestacker 1d.. My c'a's'e y`conveyor ltlhas 'at one-end, .preferably Zthe fentrance end, japairfof spaced supports l121and1 3 adapted to contact'the oor.

Attached-to saidfsupp'orts varespaced lguide lrails '1'4 and 15 *having cross V-merribe'rs YA1ll6 extending therebetween.

fAn'idler shaft17is'rotatably-mounted on extension '18 i attachedfto sidewalls' datand i5 adjacent onefen'd. An-

otheror driving 'shaft F19 Ais 'rotatably mountedo'n 'conveyor `drive' unit yfratrie' '202 adjacent thef other end of case conveyor lil. A -doble chain 21 in the form of two carrying chains e'x'tendbetween shafts l1 and T19. Chain ztis connected y:to and ffnoved lby fa 'driving sprocket zz attached to driving shaft 19 turned fby the .motor 1reducer 24 suppoiftedo'r'r l:f'a'r'ne 120, fs'ai'd 'r'n'ot'or being Icon- -nccted 't'o a suitable Vso'rc'ef '-'ele'ctr'cl for y'other lpower.

Patented Oct. .211, 1.958

A pair of spaced tracks V25 mountedoncross members 16 guide the'two carryingchains 21.

Onguide rail 14 is attached v`acase stop -26 having a pivotally mounted arm 27 for stopping and holding cases on 'the conveyor while chains 21^continue yto'move-.under cases. This case stop is normally in the open-non-stop position when no cases are on the conveyor Xor in the stacker.

When the above condition exists and a Acase is `'then placed on the conveyor, the following action takesplace: The case being conveyed along the conveyor fby chains 2l moves along the conveyor until itcontactsfandmov'es switch arm 52 which operates -switch 28, which-'intum energizes air cylinder 29 causing arm27 to rnove to stop position, where it stops the next "case to comei'along'the conveyor. The original case passes the stop before 'the stop is acuated and moves on into the stacker. Switch 28 is connected to an electric source of power andair cylinder 29 is connected to a compressed air supply.

My vcase stacker 1l has abase 30 on which is mounted a pair of uprights 31 and 32 extending above the conveyor 10. A stacking dog having a bar 34 with arms 35 on each end is pivotally mounted for limited movement on each of the uprights 31 and 32. The do'ges normally are in -downward :and inward vposition fslightly above a case entering'sta'ck'er 1l.

Elevator air cylinder-'36 is mounted on'base Silla'nd has a piston shaft 3S. Mountedion theupper endof'piston shaft 33 is an elevator `frame 39 which extends between the -two conveyor 'chains21. The air cylinder is {connectedtoan electric'l'supply source and fa compressed/air supply.

Acasestop member 40is mounted onfthe-Tcase stacker base flib 'and has an-lelectricswiteh 41,whichis operated by contact with a'c'ase, when -the sto'p is i-'n fupper stop position, which is fthe"norrna" l position. lhistcontatwith a case energizes said electric fair cylinder-`36 a so enengizes air cylinder '29 'to open i"position, allowing one case to -i'move through -clase -Ast'o'p `l26. Air l cylinder 536 having Ibeen energized `when1`fswilth "lil was oper-ti'by case Contact, vmoves"-tl'l`eelevator fr'ame E3'9 slightly above stacking dog 'bars -3`4. 'At :this lpoint the 'frame tin-y ta'tsfelectric switch 42N'po`sition'edon 'pright energizing elevator air cylinder and changingitsdire'ctin of ftravt'frdm up Pto down. VAs the lelevatorframe-39 rnove'sthe ease upwardly, Athe cas'e'pivots' thelfstac'kir'lg dog bars 34 pw'ardlyand r"outwardlyfu'ntil it is slightly above them.V -Then the "stacking dogfbars "134 `fall Tlvby gravitynownwardly attac-inwardly, so that' asftheflvatc'r is lowered, the case movesl downwardly'againstth acking doggbar-s 34, Whereitis -lield"t1"rtil`r`noved iip'vvar'dly by ithen'eXt case Stlieebelow nected to an electric supply source. Switch 43 is connected to an electric supply source, to air cylinder 36 for downward operation of elevator 39, and to air cylinder 50 for moving stop member 40 to non-stop position. Switch 46 is connected to an electric supply source and to stop member 40 for raising the same to stop position. Switch 43 is also connectedwith cylinder 29 and also energizes said cylinder from closed to open position to start cycle over again.

The electrical system operation is as follows: The conveyor chain 21 which moves the cases placed thereon is moved by a driving sprocket 22 attached to a driving shaft 19 turned by a motor reducer 24 supported on frame 20 and connected to a suitable source of electrical power.

When the first case is moving on conveyor chain 2l, pivotally mounted entrance stop arm 26 of stop member 27 is in open non-stop position and permits the case to pass on until it contacts switch arm SZ which operates entrance switch 28 which in turn energizes entrance air cylinder 29 causing entrance stop arm.26 to move to stop position. Entrance switch 28 is connected to an electrical source of power and to entrance air cylinder 29 which is connected to a compressed air supply.

The case then travels until it moves onto elevator 39 and contacts exit stop member 40 and exit switch 41. Exit switch 41 is connected to an electrical source of supply and to entrance air cylinder 29 which is connected to a compressed air supply and upon contact with the case energizes entrance air cylinder 29 to move entrance stop arm 26 to open position to permit another case to pass through. On the same contact with this case exit switch 41 connected to elevator air cylinder 36 which is in turn connected to a compressed air supply en'ergizes said air cylinder 36 to move elevator 39 with its case upwardly.

When the case is moved slightly above the stacking dogs, it contacts an upper electrical switch 42 connected -to an electrical source of supply and to elevator air cylinder 36. This contact energizes elevator air cylinder 3 6 to travel with elevator 39 downwardly.

This cycle is repeated until a top case in' stacker 11 contacts switch arm 45 which operates top switch 43. This switch 43 is connected to an electrical source of supply and to elevator air cylinder 3 6 and moves it and elevator 39 downwardly to chain 21. Top switch 43 is also connected to exit air cylinder 50 connected to a compressed air supply and to exit stop member 40 movng it to non-stop position and permitting the stacked cases to pass outwardly on chain 21.

As the stacked cases pass near the exit end of the conveyor, they contact an end electrical switch arm 46', which through switch 46 is connected to an electrical source of supply and to said exit stop member 40 and energizes said exit air cylinder 50 -to move said exit stop member 40 to closed position.

Having thus described my invention, I claim:

1. An automatic case stacker comprising a frame, a case conveyor movably mounted on said frame and adapted to move cases thereon, said frame having an entrance and an exit, means engaging said conveyor and connected to an electrical source of supply for moving said conveyor, an entrance stop member pivotally mounted on said frame adjacent its entrance and in normal non-stop position to permit the rst case to pass therebeyond on the conveyor, an entrance air cylinder mounted on' said frame and connected to a compressed air supply and to said entrance stop member, an entrance electrical switch mounted on said frame slightly beyond said entrance stop member and connected to an electrical source of supply and to said entrance air cylinder for moving said entrance stop member to stop position when contacted by a case, a stacker positioned intermediate the entrance and the exit of said frame, said stacker having a pair of uprights, a stacking dog pivotally mounted on each of said uprights slightly above the height of a single case, an elevator air cylinder mounted on said stacker and connected to a compressed air supply, an elevator movably mounted on' said elevator air cylinder, an exit electrical switch, an exit stop member and an exit air cylinder connected to a compressed air supply mounted on said stacker at the portion nearest the exit of said frame, said exit stop member normally in closed position to prevent a case from leaving the stacker, said exit electrical switch in contact with said elevator air cylinder with said entrance stop member and with an electrical source of supply so that when a case contacts said eXit electrical switch, said entrance stop member is moved to open position to permit entry of another case, and said elevator air cylinder is energized to move said elevator upwardly with its case slightly above said stacking dogs, an upper electrical switch mounted on one of said uprights slightly above said stacking dogs, connected to an electrical source of power and said elevator air cylinder and adapted upon being contacted by a case to energize the elevator air cylinder and change the travel of said elevator to move downwardly to the conveyor level, said dogs upon being released from contact with the case, moving downwardly and inwardly to support the case moving downwardly thereagainst, the cycle being repeated until the cases are stacked high enough for the top case to contact a top electrical switch mounted high on said stacker, said top electrical switch connected to an electrical source of supply, to said upper electrical switch for moving the elevator downwardly to the conveyor level, and to said exit stop switch to energize said stop air cylinder to move exit stop member to open position and permit the stacked cases to pass from the stacker toward the exit end of the frame, and an end electrical switch mounted on said frame adjacent the exit connected to an electrical source of supply and to said exit stop switch and said exit air cylinder upon being contacted by said stacked cases t0 energize the exit air cylinder to move said exit stop member to closed position.

2. In an automatic case stacker, a case conveyor having an entrance and an' exit, a stacker positioned intermediate the entrance and the exit of said conveyor, said conveyor having means for conveying cases from said entrance to said stacker and from said stacker to said exit, an entrance stop member pivotally mounted on said conveyor adjacent its entrance and adapted to be in non stop position to permit the first case to pass thereby, an entran'ce air cylinder mounted on said conveyor and connected to a compressed air supply and said entrance stop member, an electrical switch mounted onsaid conveyor beyond said stop member and adapted upon being contacted by a case to move said entrance stop member to closed position, said stacker havin'g a pair of uprights, a stacking dog pivotally mounted on each of said uprights, an exit stop member pivotally mounted on said stacker and electrically connected with said entrance stop member, an exit air cylinder mounted on said stacker and connected to a compressed air supply and to said exit stop member, an elevator air cylinder mounted on said stacker and connected to a compressed air supply, au elevator movable by said air cylinder within said uprights and electrically connected to said exit stop member, said exit stop member upon being contacted by irst case adapted to en'ergize said elevator air cylinder to move said elevator upwardly with said iirst case until above said dogs, an upper electric switch electrically connected to said elevator and positioned on one of said uprights slightly above said dogs and adapted upon being contacted by said iirst case to energize the elevator air cylin'der to move the elevator downwardly for the second' case, said iirst case being held above by said dogs, said upper switch also connected -to and adapted to energize said entrance air cylinder to move said entrance stop member to open position to permit a second case to pass thereby, the cycle being repeated until enough cases are stacked to contact a top electrical switch positioned ad- 5 jacent the top of said upright structure, said top switch connected to and adapted to energize said elevator air cylinder to move the elevator with its stack of cases downwardly to said conveyor and connected to and adapted to energize said exit air cylinder to move said exit stop 5 member to non stop position' to permit said conveyor to move the stack of cases to the exit.

6 References Cited in the file of this patent UNITED STATES PATENTS 2,376,176 Neja May 15, 1945 2,687,813 Verrinder et al. Aug. 31, 1954 2,770,373 Verrinder et al. Nov. 13, 1956 

